Reservoirdog

As with virtually all crit vs spell dmg debate, there is no linear function, so the amount of +dmg you have, determines how much +dmg equals 1% crit. The more +dmg you have the more useful this gem will be. What i have found to work pretty well, is to simplify the math. What i do, when i dont feel like writing up a HUGE algebraic formula is look at percentages. If u know the % of dps increase, you dont need to do the rest of the algebra . mana effeciency is a diff story however, so i will not be discussing that now(clear cast ect.)

Average dmg= average lb dmg* (hit%) + [(hit %) * (crit%) * average lb dmg]

First thing first, maxing hit is vital as it makes math SOO much easier, and is the best stat. 1% hit = 1% dps increase, plain and simple. 1% crit = 1% dps increase * hit percent. so at hit cap (100%) 1%crit now equals 1% dps increase.

Like i stated earlier the % increase in dps from +dmg dps VARIES. for example if your lb hits for 1800, you would need less +dmg to equal 1% crit than if you have an average lb of 2000. However +18 dmg will not be a 1% dps increase if you average 1800 dmg on lb, as you must account for crits, which will add 36 dmg. You can use the equation above to determine the value of +dmg as well as average dmg, just substitue average lb dmg with how much +dmg u are adding.


Damage increase from +dmg= +dmg* (hit%) + [(hit %) * (crit%) * (+dmg)]

These are just very crude equations, and do not incorporate talents etc. I know there are alot of "mistakes" and that these numbers are not exact, but they do give the basic idea, and they show you the general trend of dimishing returns on +dmg as compared to hit/crit. Using this you can easily figure out how much dmg the different meta gems will give you depending on your own stats.

I will now show an approximate % of dps gained by the original poster, using the stats that he gave. If the meta gem gives 80 spell dmg (according to original poster 40dmg @3% so 80dmg @6% increase, given that average lb hits for 1800) you must multiply this by your crit %, as you would only get the spell dmg on crits. So at 50% crit you would have 40 +dmg from this gem if it is 206% dmg(which i highly doubt). plugging this into the equation i have gives you:
40 *100% + (100% *50% *40) = 60 dps increase

%damage increase= 60(dmg increase)/1800(average dmg b4 increase) = 3.33% damage increase

However at 30% crit the damage increase is more like this:
40*100% + (100% *30% * 40) = 52 dps increase
% damage increase= 52/1800 = 2.88%

If the meta gem only gives 203% or 201.5%, all you have to do is divide the % dps increase by 2 or 4 respectively.

Hopefully this helps somebody, and i would appreciate any constructive input. As i stated earlier i know there are alot of things missing, but this is a basic starting point.